Elevator motion alert system

ABSTRACT

An elevator motion alert system for alerting a mechanic working inside a hoistway comprises a self-power-generating car beacon mounted on an elevator car, a self-power-generating counterweight beacon mounted on a counterweight, and a mobile device carried by the mechanic for receiving signals transmitted from the car beacon and the counterweight beacon and for providing an alert to the mechanic whenever the elevator car or the counterweight is approaching.

BACKGROUND

This invention generally relates to an elevator system. Moreparticularly, this invention relates to an elevator motion alert systemfor alerting a mechanic working inside an elevator hoistway.

Maintenance and repair of elevator systems may require a mechanic toenter the elevator hoistway. The mechanic may need to work within thepit at the bottom of a hoistway, on top of the elevator car or at anintermediate location within the hoistway between the pit and theoverhead. Mechanics may be faced with dangerous situations caused by amoving elevator car and a moving counterweight.

For example, a mechanic working on top of the elevator car must avoidcollision with a passing counterweight. When working in the pit, themechanic must avoid collision with either a car or a counterweightmoving downward into the pit. When working in an intermediate locationbetween the pit and the overhead, the mechanic must avoid collision witheither a car or a counterweight passing by.

WO 2008/082380 discloses a warning system for mechanics working insidean elevator hoistway which senses elevator cab position within thehoistway and senses the presence of the mechanic. A mechanic willreceive a voice-based warning message of approaching danger based uponthe sensed elevator and mechanic positions. US 2017/137256 A1 disclosesan elevator motion alert system configured to alert mechanics workinginside an elevator hoistway which detects motion of an elevator car orcounterweight and broadcasts a pressure wave indicative of elevator caror counterweight motion. An electronic device receives the pressure waveand alerts the mechanic.

In these prior art systems, various devices for sensing andcommunicating the position or motion of the elevator car, counterweightand/or mechanic are necessary and power supplies and wiring for signalcommunication are required. Installation of such devices in existingelevator systems would require additional costs and time since rewiringwould be necessary. Further, the location of such devices would belimited.

In view of the above and other considerations, there is a need forproviding an elevator motion alert system for alerting a mechanicworking in an elevator hoistway which is easy to install in existingelevators.

BRIEF SUMMARY

According to one embodiment of the invention, an elevator motion alertsystem for alerting a mechanic working inside a hoistway comprises aself-power-generating car beacon mounted on an elevator car, aself-power-generating counterweight beacon mounted on a counterweight,and a mobile device carried by the mechanic for receiving signalstransmitted from the car beacon and the counterweight beacon and forproviding an alert to the mechanic whenever the elevator car or thecounterweight is approaching.

According to another embodiment of the invention, a method for alertinga mechanic working inside a hoistway comprises mounting aself-power-generating car beacon on an elevator car and aself-power-generating counterweight beacon on a counterweight, receivinga signal transmitted from the car beacon and/or the counterweight beaconand providing an alert to the mechanic whenever the received signalindicates that the elevator car or the counterweight is approaching.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C are schematic views of an elevator system including theelevator motion alert system of the present invention with the mechanicin the pit of the hoistway.

FIG. 2 is a flowchart showing a sequence performed by an application ofa smart phone of the elevator motion alert system of FIG. 1.

FIGS. 3A to 3C are schematic views similar to FIGS. 1A to 1C with themechanic on top of the elevator car.

The detailed description explains embodiments of the invention, togetherwith advantages and features, by way of example with reference to thedrawings.

DETAILED DESCRIPTION

FIG. 1A schematically shows selected portions of an example elevatorsystem 1. An elevator car 2 is connected to a counterweight (CTW) 3 by aplurality of hoisting ropes 4. The ropes 4 extend over a traction sheave5, which is driven by a machine (not shown), and a deflector sheave 6.Traction between the traction sheave 5 and the ropes 4 drives the car 2and the counterweight 3 vertically through a hoistway 8.

A governor device 9 prevents the elevator car 2 from exceeding a maximumspeed. The example governor device 9 includes a governor rope 10 thattravels with the elevator car 2. A governor sheave 11 and a tensionsheave 12 are located at opposite ends of a loop formed by the governorrope 10. The configuration of the elevator system components may varyfrom this example in various aspects. In other words, the invention isnot necessarily limited to the example elevator system configuration orthe specific components of the illustration.

An elevator motion alert system of the present invention comprises afirst beacon B1 on top of the elevator car 2, a second beacon B2 on thecounterweight 3, a third beacon B3 on the tension sheave 12 of thegovernor device 9 and a mobile device 14 held by the mechanic 15. Themobile device 14 is a smart phone in this embodiment, but may be anykind of device carried or worn by the mechanic including but not limitedto a cell phone, tablet, lap top computer or a wearable device such as asmart watch or smart glasses. The mobile device may also be a dedicateddevice provided as a headphone, earphone, badge, belt, helmet or cap orin clothing such as a vest or uniform.

The beacons B may be Bluetooth® low energy beacons which use Bluetoothlow energy (BLE) proximity communication technology to periodicallytransmit signals including ID information via radio waves. Each beacon Bmay be identified by a unique ID. The coarse distance between each ofthe beacons B and the smart phone 14 may be determined by adistance-dependent intensity level of the radio waves received by thesmart phone 14. The distance-dependent intensity level may be theReceived Signal Strength Indication (RSSI).

Further, the approaching or departing of the beacons B with respect tothe smart phone 14 may be determined by the change in thedistance-dependent intensity level of the radio waves. When theintensity level is increasing, the beacon B will be moving toward thesmart phone 14. When the intensity level is decreasing, the beacon Bwill be moving away from the smart phone 14.

The beacons B respectively have power generating functions which convertvibrational energy into electric power. The beacons B generate power andtransmit signals whenever vibrational energy is provided to the beaconsB, that is, whenever the object on which the beacon B is mounted moves.Since the beacons B are compact and lightweight, they may easily beattached to the car 2, counterweight 3 or tension sheave 12 such as bymagnets or double-sided tapes.

The smart phone 14 has an application program for receiving signals fromthe beacons B and determining the distance-dependent intensity level ofthe received radio waves. Upon receiving a signal from the one or aplurality of the beacons B, the application will identify each beacon Bby the ID information included in the signal and determine theapproaching or departing of the beacon B based on change in thedistance-dependent intensity level of the radio waves as describedabove. The application will provide an alarm and/or a message inresponse to the signals from the beacons B as will be described in moredetail below.

FIG. 2 is a flowchart showing the sequence performed by the applicationprogram of the smart phone 14. When the mechanic 15 is in the hoistway8, the application checks if signals are received from any one ofbeacons B1, B2, B3 (step 101). If no signals are received, it indicatesthat the elevator system 1 is not moving (step 102) and no alarm isgiven to the mechanic 15 (step 103).

If a signal is received from any one of beacons B1, B2, B3 in step 101,it indicates that the elevator system 1 is moving (step 104). Theapplication provides an audible alarm No. 3 and a voice message “theelevator is moving” (step 105) to the mechanic. Next, it is checked ifthe radio wave intensity of signals received from beacons B1 or B2 arelarger than a set level S1 (step 106). If so, it is checked if the radiowave intensity of beacon B1 is increasing (step 107). If the radiointensity of beacon B1 is increasing, it indicates that the elevator car2 is approaching (step 108) and the application provides an alarm No. 1and a voice message “the car is approaching” to the mechanic (step 109).

If the radio wave intensity of beacon B1 is not increasing in step 107,it is checked if the radio wave intensity of beacon B2 is increasing(step 110). If the radio wave intensity of beacon B2 is increasing, itindicates that the counterweight is approaching (step 111) and theapplication provides an audible alarm No. 2 and a voice message “thecounterweight is approaching” to the mechanic (step 112).

If the radio wave intensity of signals received from beacons B1 or B2are not larger than a set level S1 in step 106 or if the radio waveintensity of beacon B2 is not increasing in step 110, it indicates thatthe car and counterweight are not approaching (step 113) and the audiblealarm No. 3 and the voice message “the elevator is moving” is continued(step 114).

FIGS. 1A to 1C show how the elevator motion alert system works when themechanic is in the pit P at the bottom of the hoistway 8. In FIG. 1A,the elevator car 2 is moving upwards away from the mechanic 15 and thecounterweight 3 is in the proximity of the mechanic 15 and is movingdownwards towards the mechanic 15. The smart phone 14 receives signalsfrom beacons B2 and B3, detects that the radio wave intensity of beaconB2 is larger than the set level S1 and that the radio wave intensity ofbeacon B2 is increasing. In this case, the smart phone 14 provides anaudible alarm No. 2 and a voice message “the counterweight isapproaching” to the mechanic 15. The mechanic 15 may step forward toavoid collision with the counterweight 3.

In FIG. 1B, the elevator car 2 is moving downwards towards the mechanic15 and the counterweight 3 is in the proximity of the mechanic 15 but ismoving upwards away from the mechanic 15. The smart phone 14 receivessignals from beacon B2 and B3, detects that the radio wave intensity ofbeacon B2 is larger than the set level S1 but does not detect anincreasing radio wave intensity of beacon B2. In this case, the smartphone 14 provides an audible alarm No. 3 and a voice message “theelevator is moving” to the mechanic 15. This will enable the mechanic tobe aware of elevator movement and to watch out not to touch movingcomponents in the pit.

In FIG. 1C, the elevator car 2 is moving upwards and the counterweight 3is moving downwards, but the elevator car 2 and the counterweight 3 areboth a safety distance D1 away from the mechanic 15. In this case, onlythe signal of beacon B3 is received or the signal of beacon B3 and thesignal of beacon B1 and/or B2 having a radio wave intensity lower thanthe set level S1 is received. Therefore, the smart phone 14 provides anaudible alarm No. 3 and a voice message “the elevator is moving” to themechanic 15. This will enable the mechanic to be aware of elevatormovement and to watch out not to touch moving components in the pit.

The “safety distance D1” is a distance which is not immediatelyhazardous to the mechanic 15 regardless of the direction of movement ofthe elevator car 2 or counterweight 3.

FIGS. 3A to 3C show how the elevator motion alert system works when themechanic 15 is on top of the elevator car 2. The mechanic 15 may movethe elevator system 1 in an inspection mode while he or she is on top ofthe elevator car 2. When the mechanic 15 is on top of the elevator car2, the smart phone 14 will receive and detect signals from beacon B1 onthe elevator car 2 but will ignore such signals since the radio waveintensity of the signals from beacon B1 will be constant.

In FIG. 3A, the elevator car 2 is moving upwards and the counterweight 3is in the proximity of the mechanic 15 and is moving downwards towardsthe mechanic 15. The smart phone 14 receives signals from beacons B1 andB2, detects that the radio wave intensity of the beacons B1 and B2 arelarger than the set level S1 and detects that the radio wave intensityof beacon B2 is increasing. In this case, the smart phone 14 provides anaudible alarm No. 2 and a voice message “the counterweight isapproaching” to the mechanic 15. The mechanic 15 may step back to avoidcollision with the counterweight 3.

In FIG. 3B, the elevator car 2 is moving downwards and the counterweight3 is in the proximity of the mechanic 15 but is moving upwards away fromthe mechanic 15. The smart phone 14 receives signals from beacons B1 andB2, detects that the radio wave intensity of beacons B1 and B2 arelarger than the set level S1 but does not detect the increasing radiowave intensity of beacons B1 or B2. In this case, the smart phone 14provides an audible alarm No. 3 and a voice message “the elevator ismoving” to the mechanic 15.

In FIG. 3C, the elevator car 2 is moving upwards and the counterweight 3is moving downwards, but the counterweight 3 is a safety distance D1away from the mechanic. The smart phone 14 receives a signal from atleast beacon B1, detects that the radio wave intensity of beacon B1 islarger than the set level S1, but does not detect that the radio waveintensity of B1 is increasing. Therefore, the smart phone 14 provides anaudible alarm No. 3 and a voice message “the elevator is moving” to themechanic 15.

Similar alerts will be provided in situations where the elevator car 2moves as described above in relation to the counterweight 3 and thecounterweight 3 moves as described above in relation to the elevator car2.

Although beacon B3 is mounted on the tension sheave 12 in thisembodiment, beacon B3 may be mounted on a compensation sheave (notshown) in the pit P. Further to alerting the mechanic 15 of elevatormovement, the signal from beacon B3 may be used to determine if themechanic 15 with the smart phone 14 is in the pit P. Beacons B may alsobe mounted alternatively or additionally to the drive sheave 5, governorsheave 11, car sheave (not shown) or any other rotational body to alertthe mechanic 15 of elevator movement. Mounting beacon B3 on a sheave isparticularly advantageous in high-rise buildings since the mechanic 15will be alerted of elevator movement even when the elevator car andcounterweight are located away from the mechanic 15.

The alarm Nos. 1 to 3 may be a beeping sound or a buzzing sound or anykind of sound which may alert the mechanic 15. A different sound and/orsound level may be used for each of the alarm Nos. 1 to 3. For example,the sound and/or sound level of alarm No. 3 may be different from alarmNos. 1 and 2 such that the mechanic 15 may perceive that the elevatorsystem 1 is moving but the elevator car 2 and counterweight 3 is still asafety distance D1 away. However, the same sound and/or sound level maybe used for all alarms. In addition to or in place of an audible alarm,the mobile device may also provide a vibrational alarm to the mechanic.Such vibrational alarm would be particularly effective if the mobiledevice is a wearable device.

The elevator motion alert system of the present invention allows readyinstallation to existing elevators without the need of rewiring and maybe easily mounted where required. Further, since the beacons areself-power-generating, it is not necessary to periodically exchangebatteries which would require a mechanic to enter the hoistway each timebatteries are to be exchanged.

Furthermore, since the elevator motion alert system of the presentinvention makes detections based on the distance-dependent intensitylevel of the radio waves, i.e., the estimated distance between thebeacons B and the smart phone 14, it is possible to avoid collisions notonly on top of the elevator car or in the pit but also at intermediatelocations between the pit and the overhead.

Although the present invention has been described in relation to anelevator system with one elevator in one hoistway, the present inventioncan also be applied to a group elevator system with a plurality ofelevators sharing one hoistway. In this case, the mechanic will have arisk of collision with the car or counterweight of adjacent elevators.The beacons of adjacent elevators may be distinguished from the beaconsof the elevator the mechanic is working at by a unique ID. The mechanicmay step away from an adjacent elevator in response to an alarm ormessage that a car or counterweight of an adjacent elevator isapproaching.

While the invention has been described in detail in connection with onlya limited number of embodiments, it should be readily understood thatthe invention is not limited to such disclosed embodiments. Rather, theinvention can be modified to incorporate any number of variations,alterations, substitutions or equivalent arrangements not heretoforedescribed, but which are commensurate with the spirit and scope of theinvention. Additionally, while various embodiments of the invention havebeen described, it is to be understood that aspects of the invention mayinclude only some of the described embodiments. Accordingly, theinvention is not to be seen as limited by the foregoing description, butis only limited by the scope of the appended claims.

What is claimed is:
 1. An elevator motion alert system for alerting amechanic working inside a hoistway, comprising: a self-power-generatingcar beacon mounted on an elevator car; a self-power-generatingcounterweight beacon mounted on a counterweight; and a mobile devicecarried by the mechanic for receiving signals transmitted from the carbeacon and the counterweight beacon and for providing an alert to themechanic whenever the elevator car or the counterweight is approaching;a self-power-generating sheave beacon mounted on a sheave; wherein themobile device is configured to receive signals transmitted from thesheave beacon and provides an alert whenever the sheave is rotating. 2.The elevator motion alert system of claim 1, wherein the sheave beaconis mounted on a sheave positioned in the pit of the hoistway.
 3. Theelevator motion alert system of claim 1, wherein the beacons generatepower and transmit signals whenever vibrational energy is provided tothe beacons.
 4. The elevator motion alert system of claim 1, wherein thebeacons are Bluetooth low energy beacons.
 5. The elevator motion alertsystem of claim 1, wherein the mobile device detects signals receivedfrom at least one of the car beacon and the counterweight beacon whichhave a radio wave intensity equal to or larger than a threshold S1. 6.The elevator motion alert system of claim 5, wherein the mobile deviceprovides an alert to the mechanic when the radio wave intensity of thedetected signals are increasing.
 7. The elevator motion alert system ofclaim 1, wherein the mobile device is a smart phone, cell phone, tablet,lap top computer or a dedicated device.
 8. The elevator motion alertsystem of claim 1, wherein the alert is at least one of an audible alertand a voice message.
 9. A method for alerting a mechanic working insidea hoistway, comprising: mounting a self-power-generating car beacon onan elevator car and a self-power-generating counterweight beacon on acounterweight and a sheave beacon on a sheave; receiving a signaltransmitted from at least one of the car beacon, the counterweightbeacon and the sheave beacon; and providing an alert to the mechanic atleast one of (i) whenever the received signal indicates that theelevator car or the counterweight is approaching and (ii) whenever asignal from the sheave beacon is received.
 10. The method of claim 9,further comprising: detecting a signal received from at least one of thecar beacon and the counterweight beacon which has a radio wave intensityequal to or larger than a threshold S1; and providing an alert to themechanic when the radio wave intensity of the detected signal isincreasing.
 11. The method of claim 9, wherein the sheave beacon ismounted on a sheave positioned in the pit of the hoistway.
 12. Themethod of claim 9, wherein the beacons generate power and transmitsignals whenever vibrational energy is provided to the beacons.
 13. Themethod of claim 9, wherein the beacons are Bluetooth low energy beacons.14. The method of claim 9, wherein providing an alert to the mechaniccomprises providing at least one of an audible alert and a voice messageto the mechanic.